Automatically-adjustable grinding wheel



April 17, 1928.

A. M. FULLER AUTOMATICALLY ADJUSTABLE GRINDING WHEEL Filed Feb. 2'7, 1922 7 Sheets-Sheet 1 lNI/E/VTOR W 711% ATTORNEY i April 17, 1928. 1,666,237

A. M. FULLER AUTOMATICALLY ADJUSTABLE GRINDING WHEEL Filed Feb. 2'7, 1922 7 Sheets-Sheet 2 WITNESSES: l/VVE/VTOR am 71451! Mazda. w.

V ATTORNEY April 17, 1928.

A. M. FULLER AUTOMATICALLY ADJUSTABLE GRINDING Filed Feb. 27, 1-922 7 Sheets-Sheet 3 lA/ l/E/V TOR WITNESSES.

, ATTORNEY April 17, 1928.

A. M. FULLER AUTOMATICALLY ADJUSTABLE GRINDING WHEEL Filed Feb. 27, 1922 7 Sheets-Sheet 4 |-|||||l|| lllll III II Fll wvmro/e mm m Em W/TNESSES Mah ATM/DVD A. M. FULLER AUTOMATICALLY ADJUSTABLE GRINDING WHEEL April 17, 1928. 1,666,237

Filed Feb. '27. 1922 7 Sheets-Sheet 5 WITNESSES: INI/E/VTOI? BY I WW ATTORNEY April 17, 1928. 1,666,237

A-. M. FULLER AUTOMATICALLY ADJUSTABLE GRINDING WHEEL Filed Feb. 27. 1922 7 Sheets-Sheet 6 M FIG. 22.

flb. 2.3. J 162 WITNESSES: I M/I/EIVTOI? W ATTORNEY April 17, 1928. l 1,666,237

A. M. FULLER AUTOMATICALLY ADJUSTABLE GRINDING WHEEL Filed- Feb. 27, 1922 7 Sheets-Sheet 7 WITNESSES: //V VE/V TOR p/ZQQM ATTORNEY Patented Apr.- 17, 1 928.

PATENT OFFICE.

ALBERT M. FULLER, OF PITTSBURGH, PENNSYLVANIA.

AUTOMATICALLY-ADJUSTABLE GRINDING WHEEL.

Application filed February 27, 1922. Serial No. 539,421.

This invention relates to abrasive grind-' the wearing down of the grinding wheel and ing machines, and particularly to means for compensating adjustment thereof to secure a constant positional relation of the rinding member to the stock being groun particularly the invention relates to machines employing a rotating abrasive grinding wheel, and the invention has for its object the provision of means to position the axis of the grinding wheel so as to keep the.

periphery thereof in constant relation tothe stock, regardless of the wearing down of the periphery of the wheel caused by the grinding operation. Stated differently, the object of this invention is to rovide automatic means by which the grlnding wheel, after being set or adjusted to a desired pos'ition, is positively moved toward the stock being ground to continuously compensate for the radial reduction of the grinding wheel caused by wear.

The many uses and advantages ,of this mechanism willbe apparent to those familiar with the art, .from a reading of the fol-lowing specification.

Referring to the drawings, Fig. 1 is a front elevation of a vertically arranged grinding apparatus embodying in a simple form the principle of this invention; Fig. 2 is a side elevation of the machine shown in Fig. 1; Fig. 3 is a horizontal section on the line IIIIII of Fig. 1; Fig. 4 is similar .to Fig.- 2, showing the relative position. of the parts after the grinding wheel has been partly worn down; Fig. 5 is a side elevation showing a modification of the machine of Figs. 1 to 4;, in that a lever arrangement is used instead of the pulleys of Fig. 1; Fig. 6 is similar to Fig. 5 except that the parts are shown in position as resulting from a material wearing down of the grinding 'wheel: Fig. 7 is a horizontal section on the line VII-VII of Fig. 5; Fig. 8 is another modification, showin a horizontally moving grinding wheel, in which the necessary adjusting force is provided by springs; Fig. 9 is a front elevation of the machine as shown in Fi 6; Fig. 10 shows another modification, 1t being a side elevation of a horizontal machine, in which is embodied a correcting device to prevent inaccuracy due to wear other than that of the grinding wheel; Fig. 11 is a plan View of the machine shown in Fig. 10; Fig. 12 is a partial side elevation similar to Fig. 10, but with g the parts in relative position IQSuIting from itsfollower; Fig. 13 is a vertical section on the line XIII-XIII of Fig. 10; Fig. 14 shows another modification, being a side ele- More\ vation of a vertically arranged grinding mechanism embodying means for correcting inaccuracy due to wear other than that of the grinding wheel, the take-up acting through a system of levers; Fig. 15 is a partlal front elevation of the machine of Fig. 14; Flg. 16 is a view similar'to that of Fig. 14'with the parts in relative position resulting from the wearing down of the grinding wheel and its follower; Fig- 17 is a modification showing a vertically movable gravity type of grinder adapted to grind the inside of cylinders; Fig. 18 is an end elevation of the machine of Fig. 17; Fig. 19

-'is a partial plan View of the machine of Fig. 17; Fig.20 is a modification comprising auxiliary springs, and a rotatable mounting for the entire grinding apparatus; Fig. 21 is a partial longitudinal vertical section through the machine 'of Fi 20; Fig. 22 is a side elevation-of a modification comprising a withdrawing lever; Fig. 23 is a side elevation of. one of the leversused in the.

modification employing levers; Fig. 24 shows the grinder of Fig. 22 in withdrawn position; Fig. 25 shows the grinder of Fig. 22 after the grinding wheel has been worn down; Fig. 26 is a vertical section on line XXVI-XXVI of Fig. 25; Fig. 27 shows a modification in which the follower is not mounted to move in line with the grinding wheel; and Fig. 28 shows the mechanism of Fig. 27 after the grinding wheel has been worn down.

In grinding machines of this type as heretofore used the adjustment of the grinding wheel to compensate for the wearing away of its periphery has ordinarily been done by hand, at intervals, by means of a screw and hand-wheel, or other similar mechanism. Where the adjustment has been automatic it has also been intermittent. Manual means of adjustmenthas the disadvantage of giving only approximate accuracy in result, since the adjustment of the grinding wheel is necessarily intermittent, and

dependent upon the personal judgment of adjustments. I For example in grinding cylinders'requiring accuracy within a limit of four one-thousandths of an inch, each inch of radial reduction of the grinding wheel would require five hundred separate adjustments' to keep within the limit, and even with that number the cylinders turned out wouldnecessarily vary as much as four onethousandths of an inch at difierent diameters; j

By'thermechanism'described in this specification' a grinding wheel maybe set or ad- 'ust'ed to a certain position, and thereafter it vwill be continuously and automatically moved towards the stock being ground as fast asthe wearing off of the periphery of the grinding wheel reduces the radius thereof. The movement of the grinding wheel towards the stock bein by and coextensive wit the reduction in radius of the ding wheel, perfect accuracy in the fi l 5 5th of grindin may be constantl maintained. Since on y one initial setting or adjustment of the grinding wheel is necessary, the invention is particularly applicable to quantity production,

governed entirely access? of the grinding wheel towards the stock is constantly limited to a distance exactly equal" many difierent forms of machines, an

the

principle may be app-lied in a reat grinding mechanism may be variously ,mounted and arranged, to operate vertically, horizontally, or at any desired angle, as will be apparent'from the following examples, which are to be understood as illustrative only, the invention being adapted to various changes and modifications of mechanism to meet special cases.

The illustrations show. grinding wheels having a straight grinding edge parallel to theaxis of the wheel, but it is to be understood that the grinding face or edge of the grinding wheel may be of any contour that may be required for grinding the stock to -any particular shape.

In Figs. 1 to 4, there is illustrated a very simple form of ravity actuated grinding mechanism embodying this invention. This comprises a rigid base 1 from which extends a Vertical V-shaped frame member 2 carrying at its to a rigid extension 3 in which is supports a, screw 4, carried by a nut 5, which seats on the top of the arm 3. Rotation of the nut 5 raises or lowers the screw, which may be locked in adjusted po- 'sition by means of a bolt 6 engaging a groove where many separate pieces are to be ground 8 through which extends a pin 9, supporting a balanced cross member 10, to the ends the same dimension, as for exarts are to to exactl ample w ere interchangeable be made byvmachinery, and w ere the fitting thereof, must be very close and accurate.

Furthermore,,. in the grinding of certain tools, and parts of machinery or instruments, where accuracy to a thousandth of an inch, or less, is required, the adjusting means herein described will be found highly valuable, since the machine having once beenset to secure the desired accuracy, reuires no furtheradjustment until an entire grinding wheel has been worn out.

The principle upon which the invention is based comprisesa circular rotatable grinding member so mounted that the axis of the of which are attached flexible cables 11. These cables extend around pulleys 12 rotatably mounted upon pins 13 fixed in the sides of a slidable block 1a. This block engages a T-headed extension 15 from the vertical frame member 2, as more clearly illustrated in Fig. 3. The cables 11 extend around the pulleys 12, and their other ends 16 engage pins 17 fixed in a slidable block The lower 7 18 which is mounted on a T-head 19 extend ing from the outer face of the blockl l. Fixedfito the lower end of the block l t is a motor M having a horizontal shaft A upon the-projectin end of which is mounte a grinding whee G.

Upon the block 18 by any suitable form of hearing, as for example the two-piece bearing formed by the cover plate 20, there is mounted a second horizontal shaft B, the projecting end of which-carries fixed thereon a follower wheel, or follower F. This follower is preferably made of a rei'istant material such as steel or fibre, raw hide, or the like, Sonia it will not be readily worn; The grinder G and the follower F are so positioned upon their respective shafts that,

their peripheries are adapted to form a tangential contact as illustrated. The slidable mounting of the block 14,which supports the to the T-head extension 19 of the block 14.

The cables 11 are fixed at one end to the cross-head 10, and after passing around the pulleys 12 are fixed to the pins 17 at their ends. These cables 11 therefore support the block 14, which carries the motor M and grinder G; The ends 16 of the cables being attached to the pins 17, fixed 1n the block 18, can onl move downward as the block 18 moves ownward. But the downward travel of this block 18'is limited by contact 1 of the periphery of the follower which bears upon the periphery of the grinder G. That is to say, the relative movement towards each. other of the shafts A and B is limitedrby the sum of the radii of the grinder G and follower F. As long as this distance .remains the same the follower F cannot move downward, the ortion of the supporting cables between t e pulleys 12 and the pins 17 remains constant, and consequently the entire apparatus mounted on the block 14 is suspended at a point determined by the length of cables between the support 10 andpulleys 12. The len h of this ortion of the cables can only e increase by the lowering of the pins 17, and these can only be lowered by reduction of the distance between centers of the shafts A and B.

As the periphery of the grinding wheel G wears ofl the follower F moves down a vertical distance equivalent to the radial reduction of the grinding wheel. This in turn permits the lowering of the ulleys 12, and consequently of the grinder The result will be that as the grinding wheel is worn off radially the follower F will move down a distance equal to twice the radial reduction'of the grinding wheel, and the grinding wheel itself will move downward a distance equal to its radial reduction. Consequently the effective periph eral grinding contact of the grinding wheel will always be maintained at exactly the same height with respect to the stock S which is being ground, and the machine grinds to the same depth, continually adjusting itself by lowering of the carrying mechanism as fast as the grinding wheel wears off.

It will be noted that when the mechanism is adjusted for operation, the cross-head 10 to which the cables are attached, becomes a fixed member in relation to the grinding contact of the periphery of the grinding wheel with the stock to be ground. A fixed member in some form is an essential component of the mechanism in any of the various modifications in which the principle of the invention may be applied.

By loosening the screw 6 and turning the nut 5, the screw 4.- may be raised or lowered as desired, and consequently. the grinding mechanism may be set to cut at any desired distance from the upper surface of the table T. By this means the machine may be set to grind at any desired thickness. If stock of varying thickness be fed under the grinder, it is possible that in case of unusual thicknesses the entire grinding mechanism may be lifted and so not secure a grinding to the required depth. In such case the stock would have to be run enough times under the grinder to reduce it to the desired thickness. But in no case can the grinder cut to a greater depth than that to which it has been adjusted, since it is positively locked by the mechanism above described so that the grinding wheel cannot go lower than its adjusted osition- Its axis will move down as fast as its periphery wears off in radial measure, and not other wise.

In such cases if the weight of the grinding mechanism is heavier than the desired pressure of the grinding wheel upon the may be used to lift stock, a counterweigl? the mechanism. By

part of the weight 0 this means the pressure of the grinding wheel upon the stock may be adjusted as require In the illustrations given in Figures 1, 2, 3. and 4 the axis of the follower moves toward the axis of the grinding wheel in the line of movement of the grinding wheel axis toward the stock to be ground. The axis of the follower may, however, move toward the axis of the grinding wheel in any direction, as the effect in any case is to lengthen the controlling cable between the pulley 12 and the cross-head 10 an amount equal to the distance the axis of the follower moves toward the axis of the grinding wheel, this distance being always limited to and co-extensive with the radial reduction of the grind ing wheel. The controlling cable between the pulley 12 and the cross-head 10 must be parallelto the line of movement of the axis of the grinding Wheel toward the stock to insure accurate adjustment.

Referring to Figs. 5,6 and 7 a machine is illustrated, in which a lever is employed in place of a pulley arrangementv as in Fig. 2, for securing the relative movement of the parts. figures comprises a rigid vertical supporting frame 25, having a rear extension 26, in which is mounted an adjustable screw 27 having. an operating nut 28 and a locking bolt 29. The upper portion of this screw is formed into a fork 30 through which extends a pin 31, which carries a crossarm 32 to the outer ends of which are pivotally attached by means of screws 33 theends 34 of levers 35, which carry at their middle pointlaterally projecting cylindrical studs 36, upon which are carried horizontal extensions 37 of vertical supporting members 38, which carry at their lower ends the slidable'block 39 upon which is mounted shaft A of the grinder 6*. A similar block 40 is likewise mounted on the frame 25, and is vertically slidable thereon, b

tl ated in Fig.7. This block 40 carries in suitable bearings the shaft B on which is mounted an idler or. follower F The grinder, and follower are in peripheral contact as illustrated in Figs. 5, 6, and 9, and the movement towards each other .of the shafts A and B is limited by the sum of "block 39 upon which is mounted the-grinding wheel are limited in their downward movement by the studs 36., at the middle points of the levers 35. The free ends 41 of these levers bear upon the top of the block 40, or extensions 42 thereof, and these ends are free to slide horizontally on these extensions. By this arrangement when the radius of the grinding wheel is reduced by abrasion the follower F 5 moves downward, keeping in contact with the grinding Wheel. This lowers the free end 41 of lever 35, which bears upon the slidable supporting block of the said follower. This lowers'the middle point of the lever, that is to say the pin 36, which in turn permits the lowering of the carrying arms 38 and consequently the block 39. The grinding wheel will be'lowered a distance exactly equal to the reduction of its radius, while the follower will be lowered a distance exactly twice the reduction in radius of the grinding wheel. Primary adjustment is made by means of the screw 27, and thereafter the horizontal level of the grinding point of Wheel G is constantly maintained regardless of wear of the periphery. Fig. 5 shows the machine as preliminarily adjusted, with a full sized grinding wheel, and Fig. 6 shows the parts in relative position after the grinding wheel has been worn down.

In Fig. 8 there is illustrated a modification of the arrangement shown in Figs. 5, 6 and 9. in that the grinding wheel G and follower F are mounted in a'horizontal frame, and are urged toward the stock to be ground by tension of a spring or springs 50. One end of this spring is fastened to an extension 51 from an adjustable screw 52, mounted in an extension 53, from the fixed frame of themachine. tached to an extension 54 from the slidable block member 55, upon which is mounted the shaft 13, carrying the follower F The grinding wheel G is mounted on shaft A? in means of a T-head connection, as'illus-.

The other-end of the spring is atmeaaar A screw 57 extends through an extension 58 from the main frame, and is controlled by a nut 59, and locked in adjusted position by means of set screw 60, as will be obvious. A fork 61. of the screw 57 carries .a cross member 62, to the ends of which are attached the ends 63 of levers 64, at the middle points of which are studs 65. The free ends 66 of the levers bear upon the rear side of extension 67 from the block 55. Qross extensions 68 of connecting members 69 engage cylindrical pins or studs 65, and the other ends of the members 69 are secured to the block 56 which carries the shaft A of the grinding wheel. Consequently the tension spring 50 constantly urges the follower F3 against the periphery of the grindin Wheel G and consequently urges the grinding wheel toward the stock being ground. As fast as the grinding wheel wears off the follower moves toward the center of the grinding'wheel, which permits the end 66 of the lever 64 to move towards the grinding wheel, and this in turn permits the grinding wheel to move toward the stock a distance equal to one-half the movement of the follower, as will be obvious. Consequently, by this arrangement, acting on the same principle as those described above, the grinding Wheel is maintained at a constant position with reference to the stock-being ground.

Referring to Figs. 10, 11, 12 and 13 a fur-' chine frame 92. The follower f is con-.

stantly urged towards the left, that is towards the grinding wheel by means of a weight W, carried on the end of a cable 74, which runs over a pulley carried in the side of the movable frame member 91, the other end being attached to the slidable block 72. The periphery of the follower f bears against the periphery of the follower F which in turn bears against theperiphery of the grinder G and consequently the pressure produced 'by the weight W tends constantly to keep the three wheels pressed together and tends to move themin their common line of centerstoward the grinding point.

A h rizontal bar 76 is mounted in an extensiofi" from the block 72 in which is housed the shaft C of the follower f, and this bar is threaded so that its position may be adjusted by means of the locking nuts 77, as will be obvious. The other end of the bar passes loosely through a guide member 78, and terminates in a fork 79, which carries a pivotally mounted cross member 80, to the ends of which are attached cables 81. These run around pulleys 82, carried on the side of block 71, and then around pulleys 83 mounted on the slidable block 70, the other ends bein fixed to lugs 84, extending from the mova le frame member 91.

By this arrangement the travel of the grinding wheel towards the stock is limited by the cables 81, one end of which is attached to a fixed point of the frame, the other end of which is attached to the cross member 80. As the periphery of the grinding Wheel G wears down the follower F moves an equal distance toward the center of the grinding wheel. This permits the forward travel of the center of the grinding wheel a distance equal to the reduction in radius caused by the wearing off. The follower f advances with follower F, and consequently the effect so far-as the cable 81 is concerned is exactly as if it were rigidly attached to the pulley 82 or block 71.

But should the follower F itself wear off from contact with the grinding wheel, and so become reduced in diameter, as indicated in Fig. 12, the secondary follower f will in that case move forward with relation to the first follower, maintaining a constant contact. This will result in the advance of the connecting rod 76 relative to the center of the follower F a distance equal to the reduction in radius of follower F, and therefore will lengthen that portion of the cables between the cross member 80 ,and the pulleys 82 an equal amount. The result will be to exactly compensate in so far as the length of cable between the pulleys 82 and 83 is concerned for the reduction in diameter of the follower F.

,In connection with this form of machine is shown a screw 85, having a hand-wheel 86, and a micrometer adjusting scale 87, with a locking bolt 88. The screw is rotatably mounted in an extension 89 from the main frame, and its threads engage an extension 90 from a sliding auxiliary base 91, mounted on T-head 92 of the main frame. This arrangement also furnishes a means of accurate adjustment of the grinding depth,.

as will be obvious. A

Fig. 12 shows the relative position of the parts after the grinding wheel and the first follower have been worn down from their original conditions as indicated in dotted lines.

In Figs. 14, 15 and 16 there is illustrated another modification of the machine, comprising a vertically movable grinder. with a secondary compensating follower, the variengages an extension 106 from an auxiliary slidable frame 107 which carries the operating part of this particular grinder and is mounted on a T-head 99 carried by base 98. Slidably mounted on the T-head of frame member 107 is a block 108 carrying the shaft A, which in turn carries the grinder G. A similar block 109 is likewise mounted on the frame 107, and it carries the shaft B upon which is mounted the primary follower F, the periphery of which is in contact with that of the grinder as previously described in connection with the other figures. The auxiliar follower f is mounted on a slidable bloc 110, which carried the shaft C Adjustable weights W may be mounted upon the block 110 in order to giveit sufficient weight. Thusthe three blocks'108, 109 and 110 are urged in the same line by gravity towards the stock S beneath the rinding wheel. The block 108 is supported by vertical members 111, attached to the block at their lower ends, and having lateral horizontal extensions 112 at their upper ends. These extensions pass over, and rest upon semi-cylindrical pins 113, positioned at the middle points of levers 114, which are pivotally mounted at one end by pins 115 to the sub-frame 107, the other ends 116 of the levers bearing upon the upper ends of slidable block members 117, which at their lower ends rest upon the upper faces of the outer ends 118 of levers 119, which at their middle points are pivotally mounted by pins 120, carried by extensions from the block 109. The other ends 121 of the levers 119 support the bottoms of vertical members 122 which at their upper ends are rigidly attached to the block 110. The free ends of all levers are circular, in this and the other figures.

By this arrangement of parts as the grinding wheel G wears off the follower F" moves down suificiently to take up the reduction in radius, and this permits the lowering of the center of the grinding wheel a distance equal to the reduction in radius thereof. This follows from the arrangement of the lever 114,the supporting of the main grinding wheel from the middle thereof, and

ment of the auxiliary follower f, which is supported by the members 122, resting upon one end of the levers 119, pivoted at their middle points to the supporting carriage of the follower F. In case of any reduction in the radius of the primary follower F,*, the secondary follower f moves downward sufficiently to take up the loss. This forces downward the end of the levers 119 upon which the supports 122 rest, and consequently the outer ends 118 of these levers are raised an equal amount, which, being transmitted through the blocks 117 raise the ends 116 of the levers 114, and consequently neutralize the effect of reduction in size of the follower F in so far as it governs the lowering of the grinding wheel G The various parts are shown in position in Fig. 14 and their relative movement caused by a reduction of the grinding wheel and primary follower is shown in F i 16.

In Figs. 17, 18 and 19 a modification is shown applying the principle of this invention to a grinder adapted for use on the 1nside of a hollow cylinder which is moved around the grinder. This comprises a base 130 having two vertical uprights 131, with a cross-head 132, the inner sides of the vertical frame having guides 133, in which is slidably mounted a block 134 which carries this particular form of grinder. An adjustable screw 135 is carried by an extension 136 from the'cross-head 132, and the screw may be locked in position by the bolt 137. Suspended from the lower end of the screw 135 by a hook 138 is a cable 139 which passes around a pulley 140 mounted between extensions 141 from the block 134. The cable passes through an opening in the block, and around a second pulley 142 mounted on a vertical extension 143 from a horizontal housing member 144 through which extends the shaft A" carrying at its outer end the grinding wheel G", and having at its other end-a pulley 145 adapted to be driven by a belt.

Pivotally mounted by pin 150 in extension 151 from the main block 134 is a laterally extending shaft 152, on the outer end of which is carried a follower F. Suitable weights W may be mounted upon avertically movable member 155, the lower end of which bears against the top of the block 134, and constantly urges it downward. It will be understood that the housing 144 is rigidly connected to the block 134, which is held in' constant vertical position by means of the guides 133 of the main frame. Consequently the shaft A" is positively maintained in horizontal position; The block 134 is suspended and positioned vertically in the guideway by means of the cable 139. As the grinding wheel G" wears away the follower F" moves downward. That loosens the cable 139, permitting the entire block 134, and the grinding mechanism carried thereby to move downward a corresponding distance, as will be obvious.

But since the follower F is mounted at the end of the shaft 152, which moves about the pin 150 as a' center, there is a slight difference between the downward travel of the follower F moving in an arc, and the amount of slack supplied to the cable 139 by this movement of the follower. This difference is compensated for by making the face of the follower F slightly curved toward its outer edge, as illustrated, so that as the grinding wheel is lowered, the point of contact of the follower and grinder will shift toward the outer edge of the follower, and the cable will be lowered a distance equal to the actual reduction in radius caused by wearing off of the grinding wheel G". If space permits, this type of machine may be made with sliding bearings for the follower, thus securing exact adjustment without modification of the face of the follower.

The. particular arrangement would not be entirely accurate, without the curved surface of the follower F", but by the compensating means above described, and by making the carrying shaft 152 of a considerable length, the results obtained will be substantially constant, and at any rate sufficiently accurate for ordinary cylinder grinding.

In Figs. 20 and 21 a modification is shown in that instead of depending upon gravity to secure the lowering of the grinding wheel, the block 134 is urged relative to the guides 133 by means of coil tension springs 160, one end of which is fastened to the block 134 and the other end of which is attached to the main frame, or to the guides 133. The principle of operation, so far as this invention is concerned is the same, but the grinding apparatus of Figs. 20 and 21 may be operated in any desired position, as for example by grinding'underneath a part, the grinding wheel being above the follower, or by rotating the entire grinding apparatus inside of a cylinder which is being ground.

In Fig. 17 the cylinder 161 must be slowly rotated about the grinding wheel as the grinding progresses, in order to bring thestock surface to be ground into contact with the grinder.

The controlling members of the mechanism mav be mounted in a wide variety of forms. For example, Fig. 22 is a side elevation of an arrangement wherein the straight controlling lever 162 is pivoted at its middle point by the pin 163 on the slidable block 175 on which is mounted the motor M carrying on one end of its shaft A the grinding wheel G. The follower F is mounted on a block 173 which is slidably mounted on T-head extension 176 of the block 17 5. The entire grinding and auto matic adjusting mechanism is mounted upon tically faced extension 171 of the auxiliary frame 164 and when the mechanism is adjusted for operation this extension 171 becomes the fixed member with relation to control of movement of the grinding wheel. The upper end of the lever 162 bears upon a vertically faced extension 172 from the slidable block 173 upon which the follower F is mounted. Cylindrical bearing lugs at the ends of the lever 162 extend laterally to engage the extensions 171 and 172, their centers being on the center line of the lever 162. These circular bearings insure accurate adjustment at all positions taken by the lever 162 as the grinding wheel wears away.

The bearing face of the extension 171 is at a right angle to the line of movement of the axis of the grinding wheel G and the bearing face of the extension 172 is at a right angle to the line of movement of the axis of the follower F The movement of the grinding mechanism is actuated by a weight W attached to the lower end of a cable 177 passing over a pulley 179 pivoted on a lug extending from the main frame 168, the other end of the cable being attached to a rigid arm 174 extending from the slidable block 175.

As the grinding wheel (it wears away, the upper end of the lever 162 in contact with the extension 172 moves toward the grinding wheel G a distance equal to the radial reduction of the latter. The lower end of the lever 162 in contact with the extension 171 move-s an equal distance in the opposite direction with relation to the block 175, permitting the latter to move an equal distance toward the stock. The axis of the grinding wheel G, which is mounted on the block 175, is therefore constantly moved toward the line of grinding contact a distance exactly equal to the radial reduction of the grinding wheel by wear.

The extension 171 carries a removable gauge or stop 170 which is adapted to form an abutment for the adjustable stop 169. The adjustable stop being onceset. the entire grinding mechanism may be withdrawn from the stock by pulling the hand lever 165. On releasing the hand lever 165 the auxiliary frame 164 returns to its former position and the line of grinding contact .on the periphery of the stock may be changed without necessitating any re-adjustment of the grinding mecha nism. This arrangement is valuable if the stock has several sections to be ground to grinding wheel is in exactly the same position as before. Thus the the samemeasurement and it is necessary to withdraw the grinding wheel to reach the different sections, as, for example, the bearings of an automobile crank shaft, the teeth of a circular saw, etc. v

If the stock' is to be ground to different dimensions, several removable gauges or sto s 170 may be used corresponding to the di erent dimensions and after once setting the grinding mechanism the articles may be ground in duplicate by inserting the appropriate gauges or stops 170 for the different sections.

It is obvious that instead of moving the auxiliary frame 164 by means of the hand lever 165, this movement may be controlled by suitable jigs or patterns acting automatically. By controlling the movement of the auxiliary frame 164 by means of a mechanism constructed on the principle of the Blanchard lathe, irregular forms may be ground in'duplicate for quantity production without necessitating any adjustment of the grinding mechanism other than the initial setting.

Fig. 23 is a side view of the controlling lever 162 showin the circular lateral extensions 178 whic engage the bearing faces of the extensions 171 and 172.

Fig. 24 shows the same arrangement as 22 but with the grinding mechanism withdrawn and held away from the stock by the pawl 179 engaging the ratchet at the lower end of the hand lever 165.

Fig. 25 shows the same mechanism as Fig. 22 but with the members in their relative positions after the grinding wheel Gr has been considerably reduced by wear, the original size being indicated by a dotted line. It will be seen that the grinding contact of the periphery of the grinding wheel is in the same position with relation to the fixed member 1 1 as is shown in Fig. 22 before the diameter of the grinding wheel has bee reduced by wear. 1

Fig. 26 is a sectional view of the mechanism on the line XXVIXXVI of Fig. 25, showing the construction of the sliding members, also the relative position of the arms 17 4 to which the cable carrying the actuating weight is attached. and the lugs 181 on which the pulleys are pivoted.

Fig. 27 shows diagrammatically an arrangement of the members in which the axis of the follower F moves toward the axis of the grinding wheel in a line at an angle to the line from the axis of the grinding wheel to the point of grinding contact 182. The grinding wheel G is mounted on a slidable frame 183 which is movable toward and from the stock S to be ground. permitting the axis of the grinding wheel to move toward the grinding contact. The follower F is mounted on a slidable block 184 having an extension 185 the bearing face of I which is at aright angle to the line connecting the axes of the grindingwheel and follower; The block 184 slides upon a T- head extension 186 of the slidable frame 183 toward the grinding wheel G as the latter wears away. The controlling lever 187 ill-- stead of-being straight as in the previous illiistrations, is composed of two equal arms the central lines of which extend at an angle from its pivotal center, the center of the pin 188 b which the lever is pivoted on the slidable rame 183.

At whatever point on the periphery of. the grinding wheel the contact with the follower maybe arranged, the angle Z of the central lines of the arms of the lever 187 extending from its pivotal point 188 is always equal to the angle Y of thehnes extendlng from the axis of the grinding wheel to the axis of the follower and to the point of grinding contact 182. The circular bearing at the end of the upper arm of the lever 187 engages the straight bearing face of the extension 185 and the circular hearing at the end of the lower arm engages the straight bearing face of the fixed member 189 which extends at a right angle to the line from the axis of the grinding wheel to the point of grinding contact 182.

As the grinding wheel G27 wears away the block 184 and the bearing face on the extension 185 move toward the grinding wheel G27 a distance equal to the radial reduction of the latter. The bearing on the upper end of the lever 187, being constantly in contact with the bearing face of the extension 185, moves an equal distance. If the frame 183 were stationary, the bearing of the lower end of the lever 187 would move away from the grinding wheel an equal distance, but since the frame 183, to which the lever is pivoted, is constantly urged toward the stock by the weight W27, the bearing on the lower end of the lever is constantly held against the bearing face of the fixed memher 189, so that the pivotal point 188 of the lever and the frame 183 carrying the grinding wheel G27 are constantly moved toward the stock a distance exactly equal to the radial reduction of the grinding wheel by wear.

Fig. 28 shows the same mechanism as Fig. 27, but with the members in their relative positions after the grindin wheel G28v by wear, the

has been considerably reduced original size being indicated by a dotted line. It will be seen that the point of grinding contact on the periphery of the grinding wheelis in the same position with relation to the fixed member 189 as is shown in Fig. 27 before the diameter of the grinding wheel has been reduced by wear.

It will be understood that the embodiments above described are illustrative only,

and that many variations in structure, and

many adaptations of' the general principle may be devised. I do not desire to be'limited i to the specific forms shown, and have not tried to illustrate all possible or' desirable forms, but believe that those shown are sufficient to inform anyone skilledin the art how to practice the invention in ajvariety of other forms. I I

I claim: a

1. A grinding mechanism comprising a circular rotary abrasive member, a circular non-abrasive rotary follower member, having a common plane of rotation with the abrasive member and contacting tangential ly at its periphery with the periphery of the abrasive member, the abrasive member being constantly urged towards the stock be- I ing ground and the follower towards the axis of the abrasive member, and a connection between the abrasive member and the follower member whereby travel of the abrasive member toward the stock is governed by travel of the follower toward the abrasive member.

2. A grinding mechanism comprising a rotary abrasive member, a rotary follower member ositioned in the plane of rotation of the a rasive member and contactin at its periphery with the periphery of the a rasive member, and a positive connection between the said abrasive and follower members whereby movement of the abrasive member toward the stock to be ground is limited by movement of the follower toward the axis of the abrasive member.

3-. A rinding mechanism comprising a rotary rasive member, a rotary follower member positioned in the same plane as and in tangential peripheral contact with the abrasive member, a movable support for the abrasive member adapted to permit it to move toward the stock to be ground, a mov able support for the follower member adapted to permit it to move toward the axis of the abrasive member, the abrasive member being constantly urged toward the stock and the follower member constantly urged toward the axis of the abrasive member, and a connecting member between the abrasive member and the follower whereby movement of the abrasive member toward the stock being controlled by movement of the foliower toward theaxis of the abrasive memer.

4. An abrading machine comprising a rotary grinding wheel, a support for the grinding wheel movable toward the stock being ground, a follower wheel contacting peripherally and tangentially wit-h the grinding wheel, a slidable support for the follower, and a positioning member carrying the support for the grinding wheel at an intermediate point, one end of said positioning member being limited in movement toward the stock by a fixed member and the abrading wheel and the latter toward the stock, and connections between themounting of the follower and the mounting of the abrading wheel and a fixed member whereby to limit movement of the abradin wheel toward the stock to a distance equa to the radial reduction of the abradin wheel.

6. In a grinding machine, t efcombination of a stationary stock-holding element, a rotatable circular abrading member having a carriage mounted to slide toward and away from the stock-holding element, a circular rotatable follower havlngits periphery in tangential contact with the periphery of the abrading member, a slidable carriage for the follower, and means positively connect.- ing the two slidable mountin s with .each other and with a fixed mem er whereby movement of the abrading member toward. the stock-holding element is controlled-by movement of the follower toward the axisof the abrading element.

7. In a grinding machine, the combination of a work-supporting element, a rotatable abrading element having a circular abrading face, one of said elements being mounted for movement toward and from the other, a rotatable follower bearing tangentially against and continuously urged to-' ward the abrading face of said abrading element, and means controlled by the position of the axis of said follower with relation to the axis of the grinding element for moving said movable element toward the other element in proportion to the diminution in the radius of the grinding element whereby the work-supporting element is continuously maintained at a fixed position I with relation to the face of the abrading element.

8. In a grinding machine, the combination of a rotary abrading grinder, a carriage therefor mounted to slide to and from the stock to be ground, a rotary follower adapted to contact at its periphery with the periphery tangentially of the grinder, a carriage for the follower slidably mounted so that the axis of the follower is movable towards the axis of the grinder, means urging the follower towards the grinder and the grinder towards the stock, and a controlling member having one end limlted in movement by a fixed member and the other towards the stock.

' member.

end limited in movement'bythe carriage of the follower, forward movement of the carriage of "the grinder being governed by movement of an intermediate point of said controlling member, whereby as the follower movestowards the axis of the grinder the latterrls permitted to move anequal 9. An abrading machine comprising a rotary grinder slidablyfmounted to move toward and from the stock being ground, a rotary follower adapted to contact tangentlally at its periphe with the periphery of the grinder and slid bly mounted so as to be movable towards the axis of the grinder, a limlting member abutting against a fixed member at one end and against the support of the followerat the other end, movement of the grinder being governed by movement of an. intermediate point of the limiting 10. In an abrading machine thecombination of a grinding wheel, a circular follower 1n the same plane and in tangential contact wlth thegrinding wheel at its periphery, each ofthe rotary members being slldably mounted, 'anda controlling member, the

movement of one end of which is limited by a fixed member, the movement 'of the other end being limited by movement of the follower, and the "movement of the grinder being limited by movement of an intermediate portion of the controlling member, whereby the grinder is constantly permitted -to move towards the stock a distance equal mounted on a movable support permitting the axis of said follower to move toward the axis of said grinding wheel, and a flexible member connecting the grinding wheel support and the follower support with each ot er and with a fixed member whereby the movement of the grinding wheel support toward the stock is constantly limited to a distance equal to the radial reduction of the grinding wheel by wear.

12. A grinding mechanism comprising a rotatable grinding wheel mounted on a movable support permitting the grinding wheel to move toward the stock to be ground, a follower the periphery of which constantly bears tangentially upon the riphery of said grinding wheel, said fo lower being mounted on a movable support permitting the axis of said follower to move toward the axis of said grinding wheel, means continuously acting to move said grinding wheel support toward the stock .to be ground and the axis of said follower toward the axis of said grinding wheel and. a flexible member attached at one end to the follower support and at the other end to a fixed member and carrying the grinding wheel support at an intermediate portion, whereby the movement of the grinding wheel support toward the stock is constantly limited to a distance equal to the radial reduction of the grinding wheel by wear.

13. In an abrading machine, the combination of a circular grinder, having a carriage mounted to be slidable to and; from the work being ground, a circular rotary follower adapted to contact tangentially with the grinder and mounted in a carriage slidable with respect to the carriage of the grinder so that the follower is free to move in the line of centers of the-two rotary members, a cable attached at one end to a fixed member and at the other end to the carriage of the follower, the carriage of the grinder being suspended from an intermediate point in the cable, whereby the grinder is constantly limited in its forward movement to a travel equal to and coincident with travel of the follower towards the axis of the grinder.

14. A grinding mechanism comprising a circular abrading member constantly urged toward the stock being ground, a circular follower member positioned in the plane of the abrading'member and constantly urged into peripheral contact therewith, and means limiting movement of the abrading member toward the stock to an amount coextensive with movement of the follower toward the axis of the abrading member.

15. In' a grinding machine, the combination of a rotatable grinding wheel mounted on a movable support permltting the grinding wheel to move toward the stock to be ground, and means whereby the movement of the grinding wheel toward the stock to be ground is constantly limited to a distance equal to the radial reduction of saidrindmg wheel by wear, said means includmg as essential elements a rotary follower on a movable support, the periphery of the follower constantly bearing upon the grinding face of the grinding wheel, and positive connections between the supports of the grinding wheel and the follower.-

16. A grinding mechanism comprising a rotatable grinding wheel mounted on a movable support permitting the grinding wheel to move toward the stock to be ound, a rotary follower the periphery of w ich constantly bearsupon the periphery of said grinding wheel, said follower being mounted on a movable support permittin of the follower to move toward t e axis of said grinding wheel, the grinding wheel being constantly urged toward the stock to be ground and the follower toward the axis of the grinding wheel, and meansconstantly limiting the movement of the grinding wheel support toward the stock to a distance e ual to the radial reduction of the grinding w eel by wear, said limiting means being controlled in operation by the movement of the follower toward the axis [of the grinding wheel.

In testimony whereof, I sign my name.

ALBERT M. FULLER.

the axis 

